Most of the gas in the Universe is a mixture of hydrogen and helium. It's thought that the initial atmospheres of most planets also start out that way. However, over billions of years, as planets evolve, the composition of their atmospheres may shift. Hydrogen can react with other chemicals, and both it and helium can be lost to space. Venus, Earth, and Mars are thought to have second atmospheres, with their original hydrogen/helium envelopes having been lost and/or transformed.

The dynamics of loss are complicated. Lighter elements are lost more easily, but hydrogen can be protected by being incorporated into molecules like methane and ammonia. The gravity of the body can help retain some molecules, and a magnetic field can limit radiation's ability to blast material out of the atmosphere. Proximity to a star will matter too, both because of the radiation it produces and because it can heat the atmosphere and expand it to where gravity's influence is less substantial.

Given all these complications, it can be difficult to know what to expect to find on exoplanets. But a study in Wednesday's issue of Nature describes observations of helium being lost from the atmosphere of an exoplanet orbiting the star LHS 1140, about 50 light-years away. Based on the rate at which the helium is being lost, we can infer something about the remaining atmosphere.

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There are some obvious big picture issues that stand between us and useful quantum computing. Issues like whether we can make enough high-quality hardware qubits to connect into the error-corrected logical qubits we need, and how we generate the states needed to perform universal computation on those logical qubits. But there are also many less prominent challenges that will need to be solved before we can perform calculations.

One of those challenges, which only affects some types of hardware, is calibration. For devices we manufacture, like superconducting qubits, there are always subtle variations among individual qubits. (This is not true when we use something like an atom to hold the qubit, but the lasers that control them can drift.) As a result, this hardware is put through a process called calibration, where we test different frequencies and amplitudes of the microwave pulses that control them to find the combination that produces the lowest error rates, and then save those settings for use in calculations.

However, you can't perform the typical calibration process while you're doing calculations, which means drift becomes an issue for long and complicated algorithms. Google, though, has figured out that it's possible to do calibration using the same data that's used for error correction.

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One of the central features of plate tectonics is the formation of new crust at mid-ocean ridges. Part of the spreading process that drives continents apart, it was arguably the discovery of these ridges that drove widespread acceptance of plate tectonics as a theory. Thanks to decades of exploration, we now have a good picture of what the crust that forms at the site of spreading looks like. But we still have an incomplete idea of how its features are actually produced.

In other words, we have a good idea of the outcome of the process, but not a detailed picture of the process itself.

That is starting to change. In 2024, a team of French scientists was able to remotely monitor a major event on the border between the Australian and Antarctic plates, only two months after they installed equipment on the ocean floor. Their data shows that most of the spreading occurred in a relatively short time window, and some key events happened without any obvious seismic activity.

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Last week, just before the US started its break for the July Fourth holiday, the Nuclear Regulatory Commission (NRC) proposed a new rule that would change how it regulated exposure to radiation. The Trump administration has been pushing to restart construction of nuclear power plants in the US, and many pro-nuclear advocates have been complaining about the US's existing regulations, portraying them as the main barrier to the flourishing of the industry. So, it had seemed likely that major revisions were coming.

Instead, the NRC's proposed new rules endorse the science behind its current rules and suggest that any problems are largely in the vagueness of the terminology that it has been using. So, instead, it's endorsing standards that are meant to accomplish the same thing, but avoid using some of the language it had relied on. Probably the clearest indication of the evolutionary change at play is that the NRC estimates the changing rules will save industry—not just power, but also medical and research applications—only about $9.5 million a year.

LNT and ALARA

There are two technical abbreviations at the center of US nuclear regulations. The first is LNT, which stands for "linear non-threshold." It's in reference to the issue of whether there's any level of radiation that is so low that it no longer produces harmful biological effects—the "threshold" in LNT. The "non-threshold" implies that it doesn't, and that's in keeping with biology, which has demonstrated that even single particles or photons of radiation can damage DNA and that the mechanisms cells have for repairing that damage are inherently error-prone. The "linear" in LNT simply describes how the impact of radiation scales directly with the dose.

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Understanding the origin of life requires addressing a collection of overlapping scientific questions. We've made a lot of progress toward explaining how simple chemicals present on an early Earth built the complex molecules used by life and how some of those chemicals built the first genetic/catalytic molecules. But we're much further from understanding a key conundrum: How did membranes end up surrounding the first cells?

It's relatively easy to make membranes spontaneously form in water, and they'll enclose anything dissolved in that water, including nucleic acids. But the membranes then cut their interior off from everything else in the solution. Any interesting chemical reactions enclosed there would eat through the raw materials and grind to a halt.

Now, a lab at the University of Minnesota has announced that it has developed a simplified system in which a membrane encloses some genetic material but can continually import new materials supplied to it. The system also spontaneously divides, producing a few generations of "offspring" before things start failing. It's still extremely dependent upon human intervention, but it might provide a new avenue to explore questions about the origin of life and what a truly minimalistic form of life might look like.

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Near the end of May, the Office of Management and Budget (OMB) proposed a new rule that would govern how the federal government handles the grants it issues, including those that fund the vast majority of scientific research in the US.

If formalized, the rule would make political priorities the prime determinant of what science gets funded and sideline the opinions of scientific experts. Grants could be canceled due to political whims, and new layers of bureaucracy would inhibit basic scientific activities like publishing papers and attending conferences. Unlike the executive orders it echoes, it would have the force of law behind it and be significantly harder to challenge in court.

Before coming into force, however, the proposal must go through a process that includes public feedback and (potentially) changes in response. The deadline for that feedback—Monday, July 13—is rapidly approaching.

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